Bukkit.getPluginManager().registerEvents(this, this);
this.npcManager = RemoteEntities.createManager(this);
//First we register the serializer that should be used
//In this case we use the YML serializer, but you can also use your own as well as the json serializer
this.npcManager.setEntitySerializer(new YMLSerializer(this));
//If we want to save all current entities, it's pretty easy:
this.npcManager.saveEntities();
//Some serializers allow single entities to be saved, i.e. the YML serializer